Question [Q] How to disable safe mode?

My phone have stucked in safe mode long time(so sad...),because the volume button are very difficult to control.I try to research some information:

frameworks/base/policy/src/com/android/internal/policy/impl/PhoneWindowManager.java
feMode= menuState > 0 ....................................." this line change into "mSafeMode = false "

So I extract system.sin from Adroid 4.3 TFT,and open it.But the file “frameworks” isn"t have base file,if I find,I also don't konw how to edit java file,replace the file and pack them...
Moreover,the file ”qwerty.kl“,if I delete the “key 114 VOLUME_DOWN"&"key 115 VOLUME_UP ",would I enter safe mode when boot?
Can anyone give me advice?I am not good at English,thanks a lot...